Radiator and cooling unit

ABSTRACT

A radiator for dissipating heat by liquid coolant flowing includes a plate including at least two flat sections parallel to each other, a flection connecting the flat sections, a passage configured within the two flat sections and the flection to allow the liquid coolant to flow from a first opening to a second opening provided at each end of the two flat sections, the two flat sections opposed to each other, and the plate including a plurality of fins; an inlet tube having an opening formed so as to fit the first opening and an end opening for allowing the liquid coolant to flow in the passage; and an outlet tube having an opening so as to fit of the second opening and an end opening for allowing the liquid coolant to flow out the passage. The outlet tube is disposed in parallel with the inlet tube.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based upon and claims the benefit of priority of the prior Japanese Patent Application No. 2008-309925, filed on Dec. 4, 2008, the entire contents of which are incorporated herein by reference.

FIELD

The embodiments discussed herein are related to a radiator and a cooling unit.

BACKGROUND

There are units configured to cool electronic components included within an electronic apparatus using a liquid coolant. Such units include those having a radiator for dissipating heat from the coolant. Such units are disclosed, for example, in Japanese Laid-Open Patent Publications No. 10-185466, No. 2007-170718, and No. 2007-192429.

Some of radiators include a tube which allows passage of a liquid coolant or a coolant in the interior thereof and a tank connected to both ends of the tube. However, when employing the unit having the radiator as described above in a compact electronic apparatus, the employment of the unit may be difficult depending on the size of the tank of the radiator.

SUMMARY

According to an embodiment, a radiator for dissipating heat by the use of liquid coolant flowing therein includes a plate including at least two flat sections parallel to each other, a flection connecting the flat sections, a passage configured within the two flat sections and the flection to allow the liquid coolant to flow from a first opening to a second opening provided at each end of the two flat sections, the two flat sections opposed to each other, the plate including a plurality of fins outside thereof, an inlet tube having an opening formed along a longitudinal direction thereof so as to fit the first opening and an end opening for allowing the liquid coolant to flow in the passage, and an outlet tube having an opening formed along a longitudinal direction thereof so as to fit of the second opening and an end opening for allowing the liquid coolant to flow out the passage, the outlet tube disposed in parallel with the inlet tube, wherein each longitudinal direction of the inlet tube and the outlet tube are in parallel with at least one of each surface of the two flat sections.

The object and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the claims.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A to 1C are explanatory diagrams of a laptop computer;

FIG. 2 is a perspective view of the cooling unit according to an embodiment of the present invention;

FIG. 3 is a diagram of an internal structure of a jacket; and

FIG. 4A is a side view of the radiator where a tube is illustrated as a section view and FIG. 4B is a perspective view of the radiator; and

FIG. 5 is a diagram around a portion of a connecting portion between a pump and the jacket.

DESCRIPTION OF EMBODIMENTS

Referring now to the drawings, an embodiment will be described.

A laptop personal computer will be described as an example of an electronic apparatus. FIGS. 1A to 1C are explanatory drawings of a laptop personal computer 1. The laptop personal computer 1 includes a display portion 2 and a body portion 3 connected to each other so as to be openable and closable. The display portion 2 includes a liquid crystal display 4. The body portion 3 includes a keyboard 5. The body portion 3 includes various electronic components built therein. FIGS. 1B and 1C are a perspective view of the laptop personal computer 1 viewed from a bottom side, and FIG. 1C illustrates arrangement of components where a bottom cover of the body portion 3 is removed. As shown in FIG. 1C, the body portion 3 includes a cooling unit 8 built therein. The cooling unit 8 cools electronic components in the laptop personal computer 1. FIG. 2 is a perspective view of the cooling unit 8 with a printed circuit board 50. The cooling unit 8 is mounted on a printed circuit board, and includes a cooling jacket 10, a pump 20, a radiator 30, and a cooling fan 40.

The cooling jacket (hereinafter, referred to as “jacket”) 10 allows a liquid coolant to flow through the interior thereof. The jacket 10 includes a case 11 a and a lid 11 b. The case 11 a and the lid 11 b correspond to a casing. The case 11 a and the lid 11 b are formed of metal having a high thermal conductivity such as copper or aluminum, for example. The jacket 10 has a flat shape. The jacket 10 comes into abutment with electronic components such as a central processing unit (CPU) 70 b, illustrated with dotted lines, which mounted on a printed circuit board 50. Accordingly, the heat of the electronic components is transferred to the liquid coolant flowing in the jacket 10.

The pump 20 allows circulation of the liquid coolant between the jacket 10 and the radiator 30. The pump 20 is a motor-driven pump. The pump 20 and the jacket 10 are in communication with each other via rubber tubes 60. The rubber tubes 60 are configured to prevent a leakage of the liquid coolant. The rubber tubes 60 are fastened by metallic belts. The pump 20 has a flat shape.

The radiator 30 dissipates heat from the liquid coolant which is heated by the jacket 10. The radiator 30 is formed of metal such as aluminum or the like, for example. The radiator 30 includes a single tube 34, which is a plate with a passage therein, a surrounding board 36, an exhaust tube or an outlet tube 32 a, and an introduction tube or an inlet tube 32 b. The tube 34 allows the liquid coolant to flow in the interior thereof and has a flat shape and assumes a substantially a U-shape. That is, the tube 34 includes two flat sections parallel to each other, a flection connecting the flat sections, a passage configured within the two flat sections and the flection to allow the liquid coolant to flow in the passage. The exhaust tube or outlet tube 32 a is in communication with the other end of the tube 34, where an opening as an end of the passage is positioned, through a side surface thereof for discharging the liquid coolant from the tube 34 through the communicating portion. The introduction tube 32 b is in communication with one end of the tube 34, where an opening as an end of the passage is positioned through a side surface thereof for introducing the liquid coolant to the tube 34 through the communicating portion. The surrounding board 36 surrounds the tube 34. The exhaust tube 32 a and the introduction tube 32 b are respectively in communication with the jacket 10. The exhaust tube 32 a, the introduction tube 32 b, and the jacket 10 are in communication with each other via the rubber tubes 60.

The cooling fan 40 includes an opening 41, and has a cooling fan 42 stored in the interior thereof. When the cooling fan 42 is rotated, air is taken into the cooling fan 40 via the opening 41, and is discharged from a vent port 46. The vent port 46 opposes the radiator 30. The air discharged from the vent port 46 is blown to the radiator 30. Accordingly, the heat dissipation of the liquid coolant in the radiator 30 is accelerated.

The printed circuit board 50 is a hard printed wiring board and has a predetermined patterning applied thereon. A plurality of electronic components are mounted on the printed circuit board 50. These electronic components generate heat when power is supplied thereto. The CPU 70 b is one of the electronic components mounted on the printed circuit board 50. The CPU 70 b is arranged so as to contact with the bottom of lid 11 b. Accordingly, the liquid coolant flowing in the interior of the jacket 10 receives heat from the CPU 70 b, so that the CPU 70 b is cooled. The jacket 10, the radiator 30, and the cooling fan 40 are fixed onto the printed circuit board 50.

The liquid coolant is, for example, water or antifreeze solution. The antifreeze solution is water added with antifreeze liquid formulation (for example, propylene glycol) which prevents freezing of water.

FIG. 3 is an explanatory drawing of an internal structure of the jacket 10 where the lid 11 b is removed from the case 11 a where the printed circuit board 50 is illustrated additional in order to clarify the understanding of the positional relationship between the cooling unit 8 or the jacket 10 and the printed circuit board 50.

Flow channels 12 a, 12 b are provided in the interior of the jacket 10. More specifically, the flow channels 12 a, 12 b are provided in the case 11 a. The flow channels 12 a, 12 b are isolated from each other so that the flow channels 12 a and 12 b do not merge with each other. Projecting portions 15 a and 16 a are provided for trapping air bubbles in the flow channel 12 a. A fin 15 b is provided in the flow channel 12 b for accelerating the dissipation of heat caused by the CPU 70 b which is disposed so as to contact with the bottom of the case 11 a.

The liquid coolant is discharged from the exhaust tube 32 a and flows through the flow channel 12 a. The liquid coolant flowing in the flow channel 12 a is sucked by the pump 20, and is discharged into the flow channel 12 b. The liquid coolant flowing in the flow channel 12 b flows to the introduction tube 32 b. The liquid coolant is sucked into the tube 34, and is discharged from the exhaust tube 32 a to the flow channel 12 a again.

Referring to FIGS. 4A and 4B, the radiator 30 will be described in detail. FIG. 4A is a side view of the radiator 30 where the tube 34 is illustrated as a section view. FIG. 4B is a perspective view of the radiator 30 where the fin 38 is omitted in order to clarify the understanding of the whole configuration of the radiator 30. As illustrated in FIG. 4A, the tube 34 includes extending portions 34 a, 34 b, and a curved portion 34 c. The extending portion 34 b is connected to the communicating portion of the introduction tube 32 b, and extends in a predetermined direction. The curved portion 34 c is continued from the extending portion 34 b. The extending portion 34 a, being continued from the curved portion 34 c, extends so as to oppose the extending portion 34 b and is connected to the communicating portion of the exhaust tube 32 a. The tube 34 is formed into a substantially U-shape when viewed from the side as illustrated in FIG. 4A. The extending portions 34 a and 34 b extend in parallel to each other.

The surrounding board 36 has a U-shape in side view and surrounds the tube 34. As illustrated in FIG. 4A, fins 38 are provided between the extending portions 34 a and 34 b, and between the tube 34 and the surrounding board 36. Accordingly, the efficiency of the heat dissipation of the radiator 30 is improved. The fins 38 are omitted also in FIGS. 2 and 3 in order to clarify the understanding of the whole configuration of the radiator 30.

Since the cooling fan 40 in FIG. 3 delivers air toward a space surrounded by the surrounding board 36 and the air passes through the interior of the surrounding board 36, hence the efficiency of the heat dissipation of the radiator 30 is improved.

Since there is only the single tube 34, the number of connecting portions of the tube 34 with respect to the exhaust tube 32 a and the introduction tube 32 b is small in comparison with the case of radiators having a plurality of tubes. Therefore, the reliability of the radiator 30 is improved by the reduction of the number of connecting points. The number of components is also reduced, so that the manufacturing cost is reduced.

As illustrated in FIGS. 4A and 4B, the exhaust tube 32 a and the introduction tube 32 b are juxtaposed or are parallel to each other, and are arranged in the direction along a virtual extended plane of the extending portion 34 b. Accordingly, the thickness of the radiator 30 in the direction orthogonal to the virtual extended plane of the extending portion 34 a or the extending portion 34 b is reduced. Accordingly, the reduction of the thickness of the radiator 30 is achieved. Therefore, the radiator 30 is easily mountable on a thin electronic apparatus such as the laptop personal computer 1.

FIG. 5 is a diagrammatic illustration of a portion around a connecting portion between the pump 20 and the jacket 10 where the lid 11 b is removed in order to clarify the understanding of the inside of the jacket 10. The pump 20 has a suction tube 22 a and a discharge tube 22 b. The suction tube 22 a is in communication with the flow channel 12 a of the jacket 10, and the discharge tube 22 b is in communication with the flow channel 12 b of the jacket 10. The liquid coolant in the interior of the flow channel 12 a is sucked into the pump 20 through the suction tube 22 a. The sucked liquid coolant is discharged from the discharge tube 22 b into the flow channel 12 b. As illustrated in FIG. 5, the suction tube 22 a and the discharge tube 22 b are connected to the jacket 10 via the rubber tubes 60. The suction tube 22 a and the discharge tube 22 b are disposed parallel to each other.

Here, oscillations of the cooling unit 8 will be described. The pump 20 sucks the liquid coolant from the suction tube 22 a, and discharges the liquid coolant from the discharge tube 22 b. In other words, a force is applied to the suction tube 22 a from the jacket 10 side to the pump 20 side, and a force is applied to the discharge tube 22 b from the pump 20 side to the jacket 10 side. Accordingly, the pump 20 oscillates due to the forces and the oscillations are transferred to the jacket 10. By the oscillations of the jacket 10, the entire cooling unit 8 oscillates. Also, the liquid coolant in the interior of the jacket 10 is introduced into the interior of the tube 34 via the introduction tube 32 b, and the liquid coolant in the interior of the tube 34 is discharged from the exhaust tube 32 a to the jacket 10. The jacket 10 oscillates also by the movement of the liquid coolant as described above as well. In this manner, the suction tube 22 a, the discharge tube 22 b, the exhaust tube 32 a, and the introduction tube 32 b are oscillation sources of the jacket 10.

However, as illustrated in FIGS. 3 and 5, the exhaust tube 32 a and the suction tube 22 a, and the introduction tube 32 b and the discharge tube 22 b are positioned substantially on the same straight line so as to extend along the same direction. Therefore, the oscillation sources of the jacket 10 are positioned on the same straight line. Accordingly, the oscillations of the jacket 10 are smaller than that where the suction tube 22 a and the discharge tube 22 b, and the exhaust tube 32 a and the introduction tube 32 b are not substantially on the same straight line. Accordingly, an oscillation noise is also restrained.

All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a showing of the superiority and inferiority of the invention. Although the embodiments of the present inventions have been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention. 

1. A radiator for dissipating heat by the use of liquid coolant flowing therein comprising: a plate including at least two flat sections parallel to each other, a flection connecting the flat sections, a passage configured within the two flat sections and the flection to allow the liquid coolant to flow from a first opening to a second opening provided at each end of the two flat sections, the two flat sections opposed to each other, the plate including a plurality of fins outside thereof; an inlet tube having an opening formed along a longitudinal direction thereof so as to fit the first opening and an end opening for allowing the liquid coolant to flow in the passage; and an outlet tube having an opening formed along a longitudinal direction thereof so as to fit of the second opening and an end opening for allowing the liquid coolant to flow out the passage, the outlet tube disposed in parallel with the inlet tube, wherein each longitudinal direction of the inlet tube and the outlet tube are in parallel with at least one of each surface of the two flat sections.
 2. The radiator according to claim 1, wherein the plurality of fins are disposed between the two flat sections.
 3. The radiator according to claim 1, further comprising a shroud around a perimeter of the plate and the plurality of fins disposed between the two flat sections and between the shroud and each of the two flat section.
 4. A cooling unit for dissipating heat by the use of liquid coolant flowing comprising: a radiator including, a plate including at least two flat sections parallel to each other, a flection connecting the flat sections, a passage configured within the two flat sections and the flection to allow the liquid coolant to flow from a first opening to a second opening provided at each end of the two flat sections, the two flat sections opposed to each other, the plate including a plurality of fins outside thereof, an inlet tube having an opening formed along a longitudinal direction thereof so as to fit the first opening and an end opening for allowing the liquid coolant to flow in the passage, and an outlet tube having an opening formed along a longitudinal direction thereof so as to fit of the second opening and an end opening for allowing the liquid coolant to flow out the passage, the outlet tube disposed in parallel with the inlet tube, wherein each longitudinal direction of the inlet tube and the outlet tube are in parallel with at least one of each surface of the two flat sections; a cooling jacket for transferring heat generated by electronic components to the liquid coolant following therein; and a pump for circulating the liquid coolant between the cooling jacket and the radiator.
 5. The cooling unit according to claim 4, wherein the pump includes a suction tube for sucking the liquid coolant in the cooling jacket and a discharge tube for discharging the liquid coolant into the cooling jacket, the suction tube and the discharge tube are disposed substantially parallel to each other, the inlet tube and the suction tube are disposed substantially on a straight line along a direction, and the outlet tube and the discharge tube are positioned substantially on a straight line along the direction.
 6. The cooling unit according to claim 4, further comprising a cooling fan for blown air toward to a space surrounded with a board.
 7. A cooling unit for dissipating heat by the use of liquid coolant flowing comprising: a cooling jacket for transferring heat generated by an electronic component to the liquid coolant; a radiator for dissipating heat from the liquid coolant, the radiator including an inlet tube for introducing the liquid coolant from the cooling jacket and an outlet tube for discharging the liquid coolant into the cooling jacket; and a pump for circulating the liquid coolant between the cooling jacket and the radiator, the pump including a suction tube for suctioning the liquid coolant from the cooling jacket and a discharge tube for discharging the liquid coolant into the cooling jacket, plate including at least two flat sections parallel to each other, wherein the inlet tube and the suction tube are disposed substantially on a straight line along a direction, and the outlet tube and the discharge tube are positioned substantially on a straight line along the direction. 